摘要
设计了一种新型的太赫兹双芯反谐振光纤,利用有限元分析法对光纤的损耗特性、双芯之间的耦合特性等进行了理论分析.结果表明,单芯反谐振光纤在一定范围内改变内包层管的排列分布,其传输特性并不会受到明显的影响,据此可以改变双芯光纤的内包层管的排列分布,从而利用模式泄漏耦合机制在太赫兹波段实现双芯反谐振光纤的定向耦合.本文通过改变纤芯距离和纤芯间的间隙大小,在2.5 THz的传输频率下实现了耦合长度为0.72 m的定向耦合,这种太赫兹双芯反谐振光纤将在太赫兹光开关、调制器和耦合器等太赫兹光学器件中具有重要的应用价值.
The THz wave has good photonic and electronic properties,and has high penetration for non-polar materials,but its own photon energy is low.In addition,the THz wave also has characteristics such as wide bandwidth and large communication capacity,thereby making the THz wave possess important academic value and wide application prospects in the fields of non-destructive testing,biomedical imaging and communication.The development of THz technology requires not only high-performance THz waveguide technology for efficient transmission of THz waves,but also important optical devices such as optical switches,modulators,and couplers that are suitable for THz bands.With the in-depth study of THz waveguide technology,researchers have proposed many high-performance THz waveguide structures,such as metal hollow core tube waveguide,parallel metal plate waveguide,photonic crystal fiber and microstructure hollow core fibers,among which hollow-core photonic crystal fibers and hollow-core anti-resonant fibers(HC-ARF)have developed rapidly in recent years.So far,THz single-mode single-polarization fiber and high-birefringence fiber have been widely studied,but the researches on the fiber structure and devices that realize THz wave directional coupling are relatively rare.In this paper,we study the influences of the arrangement and distribution of the inner and outer claddings of HC-ARF on transmission characteristics,and thus design a new type of THz dual-core antiresonant fiber.Compared with ordinary quartz fiber couplers and dual-core photonic crystal fibers,it can utilize a relatively simple structure and achieve directional coupling above 2 THz.Using the finite element analysis method to theoretically analyze the loss characteristics and coupling characteristics of the fiber,it is found that HC-ARF changes the periodic arrangement and distribution of the inner cladding tube within a certain range,which can achieve mode leakage without affecting the fiber transmission characteristics.So the THz dual-core anti-resonant fiber can be designed by using the mode leakage coupling mechanism.By changing the core distance and core gap size,the directional coupling with a coupling length of 0.72 m is realized at a transmission frequency of 2.5 THz.This terahertz dual-core anti-resonance fiber will have an important application value in terahertz optical devices such as terahertz optical switches,modulators and couplers.
作者
张尧
孙帅
闫忠宝
张果
史伟
盛泉
房强
张钧翔
史朝督
张贵忠
姚建铨
Zhang Yao;Sun Shuai;Yan Zhong-Bao;Zhang Guo;Shi Wei;Sheng Quan;Fang Qiang;Zhang Jun-Xiang;Shi Chao-Du;Zhang Gui-Zhong;Yao Jian-Quan(College of Precision Instrument and Optoelectronics Engineering,Tianjin University,Tianjin 300072,China;Key Laboratory of Optoelectronic Information Science and Technology(Ministry of Education),Tianjin University,Tianjin 300072,China;Tianjin Institute of Modern Laser&Optics Technology,Tianjin 300384,China)
出处
《物理学报》
SCIE
EI
CAS
CSCD
北大核心
2020年第20期338-344,共7页
Acta Physica Sinica
关键词
太赫兹
双芯反谐振光纤
定向耦合
耦合长度
terahertz
dual-core anti-resonant fiber
directional coupling
coupling length
